Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5b842f01ee2c449da662634363afc5213896a2c68d4e295216fa8d7195eada50' 
  AND token = 'dovmd/9DLMTrbiNyMoxjbEfZGHAzdindQAIY4YFyMMs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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