SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '142d0b7f6b54b978da6e5279b73fff96e3761b20fd22529a4400c1ef54ded62c' 
  AND token = 'V8eeVLJkK/wifP9zrxlMUUzZrWokYCNO6XSqPCffhlU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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