SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f9ad8b3a0f3d82aa2da2c35b2ed95a4e16597925ec43963e1359b17c00bb082b' 
  AND token = 'fLlRFJVcYRmejAuyEe7cl0QzbNok93dweE7pBhNbibY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00049

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}