SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bf4e86d3858126168968724817f174a534b237b5809db995752ae9cd2b94b7b0' 
  AND token = 'qOd5ZVX1J3dVGHU2fUy+G7BkNVYzbbNA73B/R0DjHAI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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