SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4a0327c3f0aa9807ce310d4a4c4e9451823138008cea564b4c87e8d2690d6a00' 
  AND token = 'RdggfSTBeW8ddDkZqu0w1KS8S8gWI4EMbTMsOeep32k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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