SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'a6c148a83bc23789e49f0c045886edc65e0e3de31cf3e1111bc959c8c4b16080' 
  AND token = 'sdzSdlpmXyZlpemWECmTHk8BlE3mRBXlzZc/u8L7tMc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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