SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dbc348281d787385d71bd8c154b992a03c8915789f95821f1f3b042c413b26e9' 
  AND token = 'xGYmYXTBoa2j/TyGec4vL/lyJtIt8G9BCSWx/azQ7pg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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