SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a7d9bca48aef848cd1b54e5d939ed2b5fd4632a1ff4412d7732d01bc9db66527' 
  AND token = 'rCbnWLZHak2QE1NsrvJqziaPWoXvvXBxgR+wtfQTUDE=' 
  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"
    }
  }
}