SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b1cd97164bec7c5879aba89f2915e68ef3c48995f53f32bc3d84ca745944e608' 
  AND token = 'Io+rsvaL4+Ly1w/NuNZxCOqPtKaQHdLCZXFtIasZw5k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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