SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '59d5536c06e8eb05465744571a08ce61854faf5832df22889ddb7cdbb476113f' 
  AND token = 'I2D6qkSnsWER0zrYiWRe1Ka28LNDqH3uE4+TKNIMMs4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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