SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b1c4afb24318b1f154c8e7d9955f5e713c60f722f91be723f63ac357a43fc388' 
  AND token = 'nN93f0KxaGuBNWIyth7PUWO3aB4eGAVGbWDfHp+Mwvw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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