SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '94cdbb4e34b60aee6fc5a5ad7de1e6fd2b2611c9b46487fb5d5e5b2e6aca125b' 
  AND token = 'kHYBeUHLEbodZrQ+5LI1ApEoWOOecSSMhfGkAwCyHq4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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