SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '2a596eb04c819ebe6e59bf4c031dee50c2ea5e2c0d5e3d19a188960b655c9edb' 
  AND token = 'E+rygfhgMkNHHHp0b+gctc8OtYKAcb0wIB/cJAseMzk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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