SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '49811d34c918e958617f8027fd50276ef6753603cb831905d75e0e95013d34da' 
  AND token = 'k/AfBxYpGrVLmqLcS/qnDa1QGKKXbrFiTInvhzx1PsA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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