SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'af3625c06e2d98685db3c0e211a35ed9cbcf35d94b348e82bd9ad93815f81006' 
  AND token = 'HiQ6bPSKf5TB5DjkJxfpiwzxQWPEXZvgSTuLn+YqYzQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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