SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ed9214affbe54128f64b91d2a7478518337fb1c6c4248162a0248efedc044f39' 
  AND token = 'XYkizZyfQi4kqCWQiOPTwcJ3llbn46EPlyvawEgHGKI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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