SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'd13d6fd4db08d689c274ea3c3089d3b770185f53909b084b880cef351d3b87dc' 
  AND token = 'b6ti76mstyqsI2hKy1J6HdxMev2HRDlYAOHBkAn52oo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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