SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '57831d46b1792e86cdfdec5bcdc26873cf3262a6880892365ca3ef5f41f3860c' 
  AND token = 'zF4LinOZPrLDnQL+JQF+SY5K62mqh56TTOzEHUjG7MA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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