SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '6006fe6832bebca22e61b15cb8c206610416b58774483f5b04cd98359da37105' 
  AND token = 'i/UDaB74JTUKr1GypyjkbLASefOZ/yeCFFjkU2t2xlU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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