SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '7d9e6f9b77a641d80392a34dafbcadadfb3884d42f35cd35ccd7d4bd1aae3992' 
  AND token = 'TEbgoUbqSJucXJ9583P6DBss07XswpFw/+oln469z88=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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