SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e8ab4e0f98caf7f50f7d7ec1ffdc9b81b11da3a5ebb0680165619e40dfe02d42' 
  AND token = 'azbwGkmBkyhG0YKXg/EZBVPsMboGxK2RlKCgK0vWIhY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}