SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '75bd6832822637b01a0a05fd4daf9569c8d1c8adf86f468212151683e21a62b6' 
  AND token = 'DzclFvDBJYuaOx3OAtMN3VqTuV9tmUEMOihjgvJ2204=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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