SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '87a8ac655c1590646c935cf783236de3a753bdbb66a6afd5b7208fee94ff611b' 
  AND token = 'PfgeKViE4CX0M+DuDDXPBvPU9q+m1iG1CGZQNFJoyM4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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