SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4e7fe38e5a89a259bb2f08d2ef98cdbd63759bbad312cd1c0d5275d6a96c88af' 
  AND token = 'viozKAJ3RsO442sj+TMnFqKSAMMarrtWwUTq885gTY4=' 
  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"
    }
  }
}