SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'b4a6d95bbb386693508c4f9fc600616987d19e2936cbebb678433a1e99aa80b0' 
  AND token = 'Y+vldYHDnEiYGdy9duC9BXJ5P5fC71nDVNGGqxH7nBo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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