SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'e8065db01086a6ec04f494268b9d3f6951df1ee8e444ccf77c0d39f086db23d4' 
  AND token = 'lh5Dcwshz94Q3FPeWhjc8CrOwHaqXC25TsljtmBsD4k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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