SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e83656df58d75019c1132444e95e2f888054bfe6dd5a1994e73a948cd69a8ee1' 
  AND token = 'PPnh7Gj/A6wXv52w1cf0sguzXuzis+7dKPwiCEYRSgk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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