SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2caa95256254eea22eca93d0fb093a9c92cfcc0bccba04dc7640cb047b1b8b62' 
  AND token = 'nz4j2FpnPILrZiI5LVgRaYYRbUoT+oESRaA41+jiyOs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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