SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '09bff38c8153266ba00d34e1e0c7e3a098d2f1253f32dc7094ef60507f44377d' 
  AND token = 'FzvvtZ66iRiOHxzjuDQV+fVwPh/+jP8KY8aHWuD0Xs4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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