SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '7f502bfdc0c6c7db1c5622c6b288ce786ba8b565b24b239a832cfad2ee8c5c6a' 
  AND token = 'y1QHeb3KdVkYJvj5Bev0ZpGKUj/7LXSqlHz/zlkxr24=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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