SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '2187de1df1142d68ac4a24c775dfb99ce1081cd51167f4066a33f5b7a0d69534' 
  AND token = '7AjI6qBOdRa9aiMpz5/TRBGbvaZW0DbRfJrBw8x/oSQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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