SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '801274c48596cbb4e0322ebde85020c20fab6bda9fa215b28571ff693432db6b' 
  AND token = 'B2cgynVuE/P7uasBCZGGrdF96Kot8BxlvMYws1DQdWY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00082

JSON explain

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