SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '9deafe46676538425303362b3bc9ee5e4cc91b94f835efd69c84dd1c6cf80f5d' 
  AND token = 'HE9pCWTAuz/Psi831EVmzs4dslmC8hJXX9hFQrQgrkI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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