SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '40214ea0d08d1dcc05a3664b92bd92867d237ce065adba686c1c59619a9bbe29' 
  AND token = 'RmH8NWcLB6kUlB/vjxVb4i8xj30aKHsu6/YVj41DdwI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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