SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '84e7dc487dd6b166d3db3fe22126df506f3175d6bf682f3eb5bcb1fc840c5a46' 
  AND token = 'OVuKhV5LGvVj6Z5GFIjtzFOipLV+/+i70dqor/mq0uw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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