SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2ea39137f964acbad691d860b78cd12a3fefb2c4eeebf2f271ef9dfb8618744f' 
  AND token = 'gYgBbv4SFpq0gZ3qZ7oYZMtoGmXuEclBYm5kKf9joFA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}