SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c077af4739d1f3fcdb2ee1e73a95a98dbd02f1d715375639190003cfd4326620' 
  AND token = 'teLNaCBXQg0MdWauEuat3GpGDYsvdpMy88GqDEFHSq0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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