SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2481acc36b530996b278831539b25b46526dc7a6a85ad4b8d289e52d0f6093b1' 
  AND token = 'ulYLVZ2a9fkKHYq9gzlalnKwVXXSwUYywGCFaG5vjVc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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