SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'cec16a825ab854325415d2096b2135d6b3d56c0de83781bbd3bdffc699277102' 
  AND token = '3i/8DHSKyfF0oW/UKvxlkCZJL3kv49XvNGjRc6bDGeo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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