SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ee3ee729358b91c2f2b8f0cbf1109a40c9f4096cf20582ba5f2bc11ce1f0c42c' 
  AND token = 'zwGbKZdOJJGqRlwwW3nJB1IV5vMjDVaY0mKS5EpCUvQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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