SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2ec2041662b74d206b3ecca335ad923feac3e25d9663cab97cfc8ce4b7d73fe3' 
  AND token = 'hCF8UyvHxWQaB1MrezkLFR7qEwM3Wx0bbfF3xNg7CjY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}