SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '025f608785bb7a1723d9ef080cfd5bbe5b61ff67bde7545fdcea975857d6a80f' 
  AND token = 'xkez0zLD3q3+NXf87hl0IFjhoptEUrx0j3p+Hn3pZEo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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