SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '1abdc6a91ea7979dce103da1fa107d417d7293d5487b1900d2ca248957edf40b' 
  AND token = '8zjPEOUXx2TMmdtuHSM/EfxlHaNSODY3Fqdyj3e5NC0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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