SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4ee6ef43d7da686da123c3cccce7f03877e7fd08c254179fd474801cf6772370' 
  AND token = 'aEJ05wRskqZewc9Zy7ftnDXLuqrnlocwTH2W8sE/qEs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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