SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '37106caa1ae4d480f697e135b689c3f12287e593c33897f5270cb7b638efda7a' 
  AND token = 'pNh0QIa49BjFOWkmXWUOHCYTSqyAfOfstf7D6gKVllg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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