SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '30e8fc0d7e0325988aa484ff3453e6d2275bed2f22f15daf8e85f6b47001908b' 
  AND token = 'NGxuOBuO2kAWBQb1uedTEtVSnqiGSm7txoJHYS7SHRM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00136

JSON explain

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