SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ec285191a6431e4bae3ebda916b6f28f17307a9c309af7b96ce53aae57d705fd' 
  AND token = 'qiHbfmpV376xloqIfdZTNNgbYuTiVymUeF/3QxlVX4w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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