SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3a08362a9619e4ccce9b59ef11b10d9928f1a4bb19964fb3f5758e7391130889' 
  AND token = 'N9galcRLVpc7SHx/yG/ejNrx+vv0gxnjiOVAuOqUwMg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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