SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '53001ac1b394e03112c5fccbf857fdd9c49007ba9882f1904d6b4299bc4c2949' 
  AND token = 'Ovpp+43DVP+9cYvFgdlx0iP5LYcB51zvho/6UHBbnXc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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