SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '5bcb07b22e1415437ec98016ade211b2eefe955a5f93e49e1c3270858ac37e79' 
  AND token = 'wmRrIJVyFD+uUP6QAVQ5xfD4dyRg69Nh0y/UsviPDJc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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