SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e9f77d5bfb1e5e74e1dccb9046751a7086f4b19e51fe1e33abd10f91a71a6c12' 
  AND token = 'Dg+CVF80tJgwHsQFW5IqhSZcd4GfbnzyRUgmBqVUNKQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00011

JSON explain

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