SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b3869ed7870d96c52c3d7565a91b12aa0454b97dd167ac81a838b6ec09356b9a' 
  AND token = '4R7otZXRUb9lIK6CDYHMqzIPDPZFfzFGH0vEAPgNjlo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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