SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '811be32f4f4169071c5297acb25bb0465863c86ef2d6af497d7cc8bbeca819e4' 
  AND token = 'D/LAWqr8Xi+paR+/tjm1bQA0U4xpIhGBarMXSsTRc6g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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