SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0f2cda8de948e6d9b3779498e9f989cc7dafc21157b53940b9596bc596e4ce46' 
  AND token = 'tJ3uldG/KgZ5zZTGybCF8iQDz4fPaYgRGWFLVaIxIFo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}