SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '19a7d7b8938a4ddf028c8dc7a1205b3764bcb30f7119c8024c804d9878d262b5' 
  AND token = 'qjbS30z1t1cUusisuoD+xkId0kMkN5mV4ZA5+UMtuB0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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