SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '93936cf7866472c238f880909c92c24f131e3505875a42b6837283fb9db3a375' 
  AND token = 'y1Zqx24Hja7zDuYKbgNUT0q+Ao7ZhAoRIjsgLM/BAG4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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