SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e3a037f8517d24b07553ff3e12af1490c2537f70ac9dd6e5e16045d48c80659d' 
  AND token = 'hlgPI9kWMe9gXtQrLYxSjgNQop0FncXoW4kyHXX77z8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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