SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e3f773bb9421b7d9c1140464cd11847a4554123dcde6840654400d35606e3f6c' 
  AND token = '6suQUD0RMqxkShdYKrufzq/C5Uyut2gtvCCAlmw5O4I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}