SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a4a075e2f196de90731b1786ea9dbe8945c0c8946a38985bd5666881833cba60' 
  AND token = 'vJvSCsfDWhAbYhdg7HETPJzs8wnBN5ISpwbxmTNDL9g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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