SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '32588c81f3338ac8c2da7073c058e0ca9107b0b859e1af2f19825532899b15fb' 
  AND token = 'VspW288+1fSHoxr/dlrHsh6LRcHspekkdVNzeSST1NU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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