SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b19322114bb86bae910bad177daed1e25a3a2ea5c5d7b5e03c05068966a2520f' 
  AND token = 'iCWIYDSjwaXjpzxzQY0Fw27rgwwn1J5jKCVtkGiFJ9M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00097

JSON explain

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