SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a7db7662c42a830843c672ff3700bdf10e85918257551188b2cd4522f5cd4cc2' 
  AND token = 'Z3vcUG0h3WJDFrEmddApoG8FQiq6QByDE86twMkqEVU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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