SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'bc28d45a75b86f90c740a53cf18f29dd37ebbce8c7b10168d34958b9abcd2869' 
  AND token = 'F9OvNmY8bos3cJn4jV7fz4UZ8LUjCkukVSuCizE3haA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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