SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd29f6360bbe521653635de8e51e2c8b63943684b34cc332c561250580b106fe0' 
  AND token = 'e57oUQN6pbGmtHzSOyyeKu1LiJB7EzWeYq7Tvww7b4I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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