SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '613feeea2ab4dbcd94fcf5d9b2fdf6a972be02acb248e8649434790cdb92b2f0' 
  AND token = 'NFFzOelj9dRU0ndyFv2S9veEkyGwM8iwqGUGT6AJwCo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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