SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1791bd4b32b4ea151eb1e75ec263c5c750bd6fe2edb950bfd2e1506b9c07a37a' 
  AND token = '2uJBPuoGjRRDvkIKWxSbDQt3/XgBcUl8BOSJtAdQe8c=' 
  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"
    }
  }
}