SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fa01546ab2ec416e56b5289b2409556fbd04006d2cba0566a6b8e684a5759f97' 
  AND token = 'hER+ddvKZT2QrerfatWIildvNKyemwhOtAhklIGgeTw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00061

JSON explain

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