SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '0e6a2b398b8fc6014331fd0a28d755b10887d3fb8d9282fff4dff97dd502c41a' 
  AND token = 'kJMFdXGfJJVTBuoGxFDip2FFS7opU8Uj/ZlLD7s0tvg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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