Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '68aa4193781594243ee0371f0cd2c6dbb1459f03b51ebca5cdf289e46084894b' 
  AND token = '4x3mYgf875A6ttFEO7z0PldMIWc9rjrRq77M6i1pHZA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}