SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'eec16a06377ce2f97758615df8c7b7fc18c57b377a24da683d2c802cde0db054' 
  AND token = 'JNmIhX71xEpDEd3vfmpNgyG9wx8mq/7+FSvYpA6adcA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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