SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '44474336964b525ae5b424fd2287e93199096dec3e4b42f1ed92b0e06bf9ad7a' 
  AND token = 'D0VeRSiC+tqIC4kFER7wZKITsFNtnopPRpEhShWIT7Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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