SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c952f5da9c4f88db76170fd9a8bb6f17357c5adf22324760ff2f8920cac2701d' 
  AND token = 'mNe7YSjz7ifDErLM2Olg3y/lYCfXSo+KjC2BQqu/cNY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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