SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '28ae8513aef98cf8d56ed39c67873604774d406ab02fd95629a7934e70a36601' 
  AND token = 'qdZAr6PK/xJjpOMGqtsZ2E8kAu1H9GZr5RKweSPLgUk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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