SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7ba5dbd343bebd2fa016fb9bbb478ced39e5a3f99212eda84dfeb01ec009fa44' 
  AND token = '/ZpaNk3StnkeKBmcAemx0vqGIs3stazncpXVjAFUBWE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}