SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cc18aa2f5970781ad7cf416a952e35f2e6029bdb53024ec919a72260f4a57cd9' 
  AND token = 'MDZpRl8KxGGTt+U1aGwPIhNgLHdO9M72iRuJ2HhtGks=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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