SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '536677d583d5b6b7406e870c0922b37f29482472fa631f998a211fe5b4a061b8' 
  AND token = 'fxC9+dLa0/PGFKgBa+gUtQjg9HvJeRfXHcyGM6+pSZI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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