SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'ae613d47b962e8f1542fe109faf2b1d24e2296e0f43b6a655cbe738fd7114ebf' 
  AND token = 'RMlyOViMe+ktKZ+Nmua/5AZolsbsEHWKISB19JCupgk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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