SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2f0583fbc7d5af0be0953d73f37956c92b41844d109fe1ccffa1a40290201de5' 
  AND token = 'GjHmZQUlmu/U7qA7Hy3UWDfTnQb390wCZ3Jq/B8cRDY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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