SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c0e716e357f558ef6e5a97e1c66dda7b571c2fe45503a8c58f01d9f797564549' 
  AND token = 'okWmDdqukIc5tCiOfELonb34PlH0qv2IRWhGrNCYkrI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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