SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '4c7b3091889992a937d856771234b891e7e42a004ff920197ec4d771d69d5b90' 
  AND token = 'I3rZZIlXtIFqOwpKSecgrLb0nYtO3m8hJ3xiDfzWv4w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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