SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ce1d1d41422dc27a1227c40055010af2097a293151e559bd32402c33b7bf1f73' 
  AND token = 'uJ/0iO2NIZjgXUlPV5y3JqwNw4HBGqrpxkbmBc8wqvg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00062

JSON explain

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