SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e34a90e0218d2406f42b3f3e4a4ab70053f4ff817bd65c059a476e874882985c' 
  AND token = '3/I7TsWVyQ4a/P9B4vaAi1W4dY0HNegl5WZF0TAjR18=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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