SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '02ec9e834574f44e958bb33ac17648bb92059e232c291dfb1179de3d5c8b1bb0' 
  AND token = '+shuuL8yAGwnVssoRRFT6JsNGvC7VXjUZP3M+iyA3pw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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